Spheres Flashcards
continental
The outermost layer of Earth’s lithosphere that makes up the
Planet’s continents and
continental shelves are called contintial crust
Oceanic
The outermost layer of Earth’s
lithosphere that is found under the
oceans are oceanic crust
Two layers of the mantle
Upper and lower
Two parts of the upper mantle are recognized as distinct regions in the Earth’s interior
lithosphere and the asthenosphere.
Earth’s thin
Earth’s thin
outer shell is
broken into big pieces called
Ans- tectonic plates.
Identification of plate boundaries
By observing the pattern of volcanoes and earthquakes.
By the mapping of spreading ocean ridges and growing mountain ranges.
seafloor spreading
states that new oceanic crust forms at the
center of ocean ridges as mantle rises, melts, and erupts through underwater
volcanoes and then cool again.
Abyssal plains
relatively flat
Ocean ridges
submarine mountains
Deep ocean trenches
narrow and deep troughs
Inner core
mostly iron and solid
Outer core
Molten iron
Mantle
Mostly solid but soft rock
Atmos
A blanket of gases
Hydro
All water
Centre of earth
hotter than the outside
Heat flows through the
convection current
Convetion current
where heated material moves from warm and high pressure to cooler places and low pressure.
Convention currents within the
mantle
form due to thermal
expansion and contraction of rock.
As the mantle rock rise towards
the surface, it pushes on the crust.
As the heated rock reaches the top
of the mantle, it cools and sinks
under the force of gravity.
And the process repeats again.
This movement is called plate
tectonics and is the largest
convection current on the planet.
Transform Boundaries
Plates slide past each other…earthquake occurs
Constructive (Divergent) Boundaries
*As the plates move apart, hot mantle rises to fill in the middle and partially melts due to decrease in pressure
new oceanic crust is created
he boundaries are known as constructive plate boundaries
divergent
2 contenential is volcano
2 ocean sea floor spreading, mid ocean ridge
